1. Field of the Invention
The present invention relates to a winding machine particularly suitable for winding of an inner-rotor type stator or the like. This application is based on Patent application No. Hei 9-78454 filed in Japan, the contents of which are incorporated herein by reference.
2. Description of the Related Art
Examples of conventional winding machines, used for manufacturing a stator of a stepping motor or the like, are disclosed in the following publications:
Japanese patent application, first publication, No. Sho 60-96155 ("Winding machine"); and PA1 Japanese patent application, first publication, No. Sho 61-266050 ("Winding machine").
In the winding machine disclosed in the first example, Sho 60-96155, as shown in FIGS. 2 and 3 of the publication, cylindrical needle shaft 4 which is mounted on base 7 such that the needle shaft can be moved in a direction of the cylinder axis and can be rotated in its circumferential direction, and needle 3 is provided on the head of the needle shaft 4 in a direction perpendicular to the cylinder axis of the shaft 4. Wire 6 is inserted into the empty hole of cylindrical needle shaft 4, and passes through and is output from needle 3. The wire is wound onto winding section 2 on core 1 held by core holder 8 which has a function of index rotation. The winding operation is realized by a stroke in the axial direction and an oscillating (or reciprocating) motion in the circumferential direction of the needle shaft 4. In the winding machine, pin 17 is fixed to the above needle shaft 4 via holder 17 in a direction perpendicular to the axis of the shaft, and taper cone 18 is eccentrically provided in parallel to the axis of pin 17 also on base 7. The taper cone 18 is rotatable using a driving machine via rotational axis 19 and bearing 20. Taper bearing surface 23 is arranged on this taper cone 18, with an angle of 1/2 of the oscillation angle necessary for an oscillating motion of needle 3, with respect to the line of the rotational center of the taper cone. L-shaped bracket 24 is mounted on the taper bearing surface 23 and the above pin 17 is coupled via spherical slide bearing 27 to the bracket 24.
In the above-explained winding machine, when a motor (not shown) as a driving machine is rotated, L-shaped bracket 24 is rotated and needle shaft 4 coupled to the bracket 24 via the spherical slide bearing 27 and pin 17 makes a reciprocating motion. As a result, elliptical locus line A drawn by needle 3 is obtained and wire 6 output from needle 3 is wound around winding section 2 of core 1.
On the other hand, winding machine 10 of the second example, disclosed in Sho 61-266050, as shown in FIGS. 1-6 in the publication, comprises main rod 11 mounted to base C in freely sliding and rotating form; head 13, mounted to one end of the main rod 11, to which freely movable nozzle 12 for delivering and letting (lead) wire A off is mounted; driving shaft 14 mounted on the base C, along a direction perpendicular to the main rod 11; motion converting mechanism 15, disposed between the driving shaft 14 and main rod 11, for rotationally moving nozzle 12 around core W by reciprocatively moving main rod 11 along its length and also around its axis in accordance with rotation of driving shaft 14; and traverse mechanism 16 for adjusting a winding distance of wire A by adjusting the amount of projection of nozzle 12. General structural elements of traverse mechanism 16 are sub-rod 17 frictionally engaged into main rod 11; a group of toothed wheels 18, provided between one end of the sub-rod 17 and the nozzle 12, for moving nozzle 12 along a direction of its length in accordance with relative rotation of the sub and main rods 17 and 11; and cam 19, coupled to the other end of sub-rod 17, for relatively rotating the sub and main rods 17 and 11.
In the winding machine of the second example, when driving shaft 14 is rotated, main rod 11 is subjected to a linear reciprocating motion along the direction of its length and also to a rotational reciprocating motion around its axis within a predetermined angle of rotation. In this way, nozzle 12 of head 13 is rotationally moved around core Y.
One end of wire A is fixed to core Y; thus, according to the above operation, wire A is successively pulled from nozzle 12 and is simultaneously wound around the circumference of core Y.
Additionally, according to the relative rotational motion of the main and sub rods 11 and 17, nozzle 12 is moved in its length direction via the group of toothed wheels 18. Therefore, by shifting the position where wire A is pulled from nozzle 12 in the length direction of core Y, wire A is wound and aligned.
In the above-explained first example, the following problems have occurred.
(1) There is an advantage in that needle 3 can be subjected to both up/down (i.e., vertical) and rotational motions using a single drive motor. However, the locus of the motion of needle 3 is fixedly specified according to the rotational angle of taper cone 18 and L-shaped bracket 24; thus, it is impossible to perform winding suitable for any sizes such as outer diameter and winding thickness of winding section 2 of any different kind of core 1. PA0 (2) The locus of the motion of needle 3 is elliptical, by which the wire cannot be closely wound to winding section 2 of core 1. Therefore, the locus at winding of the wire is not stable, which tends to cause disordered winding conditions. Such a condition produces a problem in which the wire is not effectively wound within a predetermined winding area. PA0 (3) It is necessary to tie up and connect the end of wound wire A to a terminal. The tie-up operation is an additional process after winding, and there has been a demand in which the winding and tie-up operations can be performed in a single process. PA0 (4) Needle 3 is not moved in Its axial direction; thus, a p art of winding section 2 of core 1 bulges like a conga drum. Accordingly, the wire is not efficiently and uniformly wound over the whole length of winding section 2. PA0 (1) To perform winding suitable for each shape of various kinds of winding sections. PA0 (2) To realize stable winding. PA0 (3) To effectively perform winding over a predetermined winding range. PA0 (4) To easily determine a winding position. PA0 (5) To perform an operation of connecting the end of the wound wire to a terminal and a winding operation in a single process. PA0 (6) To improve operability. PA0 (7) To improve functional capability. PA0 (8) To reduce the number of working processes. PA0 (9) To improve the winding space factor. PA0 (1) The direction of the nozzle is switchable by the direction switching means; thus, an operation of connecting the end of the wound wire to a terminal and a winding operation can be performed in a single process. PA0 (2) By performing the operation of connecting the end of the wound wire to a terminal and the winding operation in a single process, (the number of) working processes can be reduced. PA0 (3) By reducing the working processes, operability can be improved. PA0 (4) The nozzle can be driven using the driving means for realizing the three-direction simultaneous driving operation. Therefore, stable winding can be realized by moving the nozzle along the shape of the winding section. PA0 (5) According to the movement of the nozzle along the shape of the winding section, winding can be effectively performed over a predetermined winding range. As a result, it is possible to improve the winding space factor. PA0 (6) the moving distance of the nozzle may be separately determined for each of the three axes, and furthermore, movement of the winding position setting means side may be additionally and simultaneously performed. In this way, a winding position can be arbitrarily and accurately determined. PA0 (7) By arbitrarily determining the winding position, winding suitable for each shape of various kinds of winding sections can be performed. PA0 (8) Functional capability can be improved according to the above properties .
On the other hand, the second example solves the above problem (4); however, the problems (1)-(3) are still not solved because it is difficult to extend a possible rage for winding.